Apparatus for making rayon cakes



March 9, 1943. H. RuBlNs'rElN l APPARATUS FOR MAKING RAYON C'AKES .FiledJuly 1, 1942 l Pw 1 Patented Mar. 9, 1943 UNETED STATES PATENT @FFMEAPPARATUS FR MAKING RAYON CAKES Harry Rubinstein, Brooklyn, N. Y.

Application July 1, 1942., Serial No. 449,338

(Cl. 'S7- 76.)

2 Claims.

`This invention relates to methods and apparatus for the manufacture ofrayon yarn, with particular reference vto that step thereof that relatesto the treatment of the so-called rayon cake.

One object of the invention is to provide for the improved making of arayon cake so as to avoid the wear or fuzziness on 'the outer portion ofthe cake, which represents rayon strand that must be discarded becauseit has been damaged.

Another object of the invention is to provide for the improved windingof a cake so that it may be washed and cleaned and then vreadily unwoundwithout tangling or tearing.

A further object of the invention is to provide improved methods andapparatus whereby the hardened filament rayon strand can .becentrifugally spun or coiled in a whirling bucket to form the cake whichis subsequently washed and dried and then rewound to form cones, skeinsand tubes as desired, the new and improved rayon kcake being produced ina simple, inexpensive manner well adapted for quantity productionwithout the resultant waste and loss of time in the manufacture of theyarn as heretofore encountered.

Other objects and advantages of the invention will become apparent asthe specicatoin proceeds.

With the aforesaid objects in view, vthe invention consists in the novelcombinations and arrangements of parts hereinafter ldescribed in theirpreferred embodiments, pointed out in the subjoined claims, andillustrated on the annexed drawing, wherein like parts are designated bythe same reference characters throughout the several views.

In the drawing: l

Figure l is a schematic perspective isometric view with parts removed,showing an apparatus embodying the invention.

Fig. 2 is a sectional view on the line 2--2 of Fig. 1.

Fig. 3 is a view in elevation showing the liner removed and expanded torelease for removal the rayon cake, a portion of which has been brokenaway.

The advantages of the invention as here outlined are best realized whenall of its features and instrumentalities are combined in one and thesame structure, but, useful devices may be produced embodying less thanthe whole.

It will be obvious to those skilled in the art to which this inventionappertains, that the same may be incorporated in several differentconstructions. The accompanying drawing, therefore, is submitted merelyas showing the preferred exemplication of the invention.

In the invention of the process, certain of the features disclosed maybe replaced by other equivalent characteristics, and certain steps maybe omitted, and the apparatus employed-is to be regarded as offered in asuggestive rather than in a limiting sense.

Referring in detail to the drawing, i denotes an apparatus embodying theinvention. The same is particularly adapted for the practise of the newmethod, which relates to the process of making rayon yarns according towhich cellulose sheets are softened by sodium hydroxide, then shredded,treated with carbon bisulphide, then with dilute sodium hydroxide,ripened, filtered, and finally expressed through minute oriiices to formfilaments which are hardened in a solution `to form a rayon strand fromwhich the cake is made. In making this cake, a bucket was whirled athigh speed to centrifugally lay the strand against the wall of thebucket, an axial reciprocating feeder in the bucket causing the coillingor winding to proceed uniformly up and down to form the cake in thegeneral shape of a tube. This cake was then washed and dried toeliminate the Vtackiness of the strand to form the finished yarn, `andthe cake was then rewound to produce' articles sold to knitters andweavers.

In accordance with theabove described process, there was provided achamber or container il, usually called a box, pot or bucket, generallycylindrical but preferably somewhat concidal for easier removal of therayon cake. This bucket was removably supported on a device l2 coaxialtherewith whereby the bucket was rotated or whirled at very high speed,and could be withdrawn from the device l2 for removal of the cakewithout stopping the operation of said device. The raw or tacky rayonstrand i3 consisting of hardened rayon iilaments was fed to the bucketby passing around a suitable rotary or pulley device it, thence through.feeder I5 comprising an eye i6 and a glass tube ll coaxial with thebucket. This feeder was axially reciprocated at a relatively slow rateby suitable means comprising an arm-like structure I8. Closing the topof the bucket was a removable cover t9 having a central opening 2t! forpassage of the feeder tube il. En operation the cake was wound bythrowing the rayon strand centrifugally against the wall Zi of thebucket Il.

the reciprocation of the feeder causing the strand' to be laidrelatively uniformly up and down.

Because the inside face of the wall 2l was very smooth, I perceived thatslippage occurred which caused excessive wear and fuzziness of the outerportion of the rayon cake, so that in rewinding it was customary todiscard between 100 and 200 yarns of each cake. A source of greattrouble in the rewinding was that the yarn was often tangled andfrequently broke. These difculties caused tremendous loss, of material,time and labor, in this industry in which production is very great.

I perceived that the wear and fuzziness of the outer portion of therayon cake could be avoided if sufficient frictional engagement wereprovided to avoid slippage as between the cake a-nd the rotary wall. Ifonly a small degree of friction were provided, the wear and fuzzinessreferred to would be aggravated, and this is the reason Why the wall ofthe bucket has heretofore been polished or formed very smooth. But arelatively substantial frictional resistance, sufficient to avoid rotaryslip, would produce a rayon cake Whose outer portion can be used aseffectively as any other part thereof. 'Ihis frictional surface may eveninclude definite projections or ridges of which a multiplicity may beprovided spaced throughout the inner surface of the rotary container.Preferably such engaging elements should be so formed as to avoidcutting or damaging the rayon strand by reason of relatively sharp orthin edges. But otherwise they may be very small in height, or as muchas one eighth of an inch high. They may be formed in some cases directlyon the wall 2i of the bucket, but are preferably formed on a removable,desirably expansible liner 22 for the bucket, as hereinafter described.

To avoid tangling of the rayon yarn upon unwinding the cake, thisinvention provides for a stratified Winding of the strand I3 in makingthe rayon cake. The principle involved is that the yarn of one strata orportion shall not readily mix with or become entangled with that ofanother strata or portion. One example of such winding is the so-calleddiamond-like reeling which is well known for other products. But suchreeling is not possible at the extreme speeds used in centrifugallywinding rayon strands, say, between 7000 and 9000 r. p. m. To accomplishsuch reeling, the speed of reciprocation of the strand feeder I5 wouldhave to be increased to a suitable relation to the rate of rotation ofthe bucket. Such a speed of reciprocation would be unduly high, becausevibratory and other difculties would be encountered, while thecentrifugal winding of the rayon strand would become difficult and leadto breakage of the strand. I prefer to substantially increase the speedof reciprocation of the feeder I5 to a reasonable degree, for example,from 40 or 50 to 80 or 100 or more reciprocations per minute, and inconjunction with this change, I arrange the projections or ridges abovereferred to so as to proproduce horizontal stratification of the outerportion of the rayon cake. Preferably the projections or ridges atdifferent elevations are horizontally offset so that the stratificationof the strands in the cake shall be angular for better distribution ofthe weight of the yarn. This structure may be provided on the bucket butis preferably formed on the liner 22 for easy removal nf the cake anddisengagement thereof from the projections. The details of theconstruction involved will now be described.

The liner 22 may -be formed of metal or composition material and isshaped to accurately lit the inside of the bucket II so as to be nonrotatably locked thereto. This may be effected by one or more keyways23, each of which may include a groove 24 in the liner and a ridge 25 inthe bucket 22. Thus the liner is readily engaged with the bucket uponinsertion, and is disengaged upon removal from the bucket. In general,the liner may accurately fit the bucket so as to be supported therebyagainst the centrifugal forces, especially if the liner is expansible.Thus when rotation of the bucket has stopped, the liner may contractlfor removal without binding in the bucket.

The liner 22 may have an annular bottom flange 26 to facilitate removalof the rayon cake therewith. It may also have an upper annular flange orlip such as 21 or other suitable means to facilitate the lifting out ofthe liner from the bucket. This flange may afford a stop to limit theinsertion of the liner to prevent binding with a conoidal bucket. Forexpansibility, the liner may be split at one section so as to open uplike a spring, or it may be diametrically split as shown at 28 so as toform relatively like sections 29 as indicated in Fig. 3. These sectionsare adapted to fit together accurately without any sea-m or break, as ifthere were no split.

Formed on the inside face of the side wall of the liner 22 is africtional gripping means for preventing relative slippage of the rayoncake or for causing a stratified Winding of the rayon strand or for bothpurposes. Accordingly the frictional means may be designed to fulfillthe desired objects. By way of example, a multiplicity of projectionsare provided; these may result by forming generally annular ridges, eachof which may form a ring or all of which may form a helix. Such ridges30 preferably lie in planes at an angle to the bucket axis and theydefine therebetween grooves 3l. These cooperate with the increased speedof reciprocation of the feeder I5 as hereinbefore described to produce atubular or so-called rayon cake 32 as shown in Fig. 3 in which the turnsof rayon of at least the outer portion of the cake are stratified, forexample, with respect to the axis of the same and in generallyhorizontal planes. These planes are at a small angle to the horizontaldetermined by the speed of reciprocation of the feeder, but this angleneed not be shown herein, the fine line showing of Fig. 3 beingsufficient. During the ywhirling of the bucket Il and its liner 22, the

rayon strand I3 is centrifugally thrown against the ridges 30 and intothe grooves 3l as the strand tends to move outward as far as possible.In consequence, the path of the strand' is undulating, the undulationslying along a circle. Preferably the ridges 30 lie at an angle ofapproximately 30 to 45 degrees with the vertical to cause ample offsetbetween the undulations of successive turns of strand.

If the projections 30 are used only to frictionally grip the rayon cakeagainst slippage, the projections need not follow the pattern shown inFig. 1 but may lie haphazard or in horizontal groups. But in eithercase, the sides of the projections should be beveled or curved so as toavoid edges which might injure or break the delicate rayon strands orcause them to catch and mar the uniformity of the reeling.

In describing the apparatus, the process -inf volved has been fullydiscussed. When the rayon cake 28 has been completed, the bucket H isremoved and the liner 22 withdrawn, expanded at its split 28, and thecake removed without interference by the projections. The cake may thenbe washed and dried, and finally rewound in the form of cones, tubes,skeins, or other commercial articles. The waste of material, time andlabor is avoided and the objects of the invention fuliilled.

The direction of winding of the rayon cake relative to the angle of theridges 3U is preferably such that in unwinding the cake, the approach isat an obtuse angle to the topside of the ridges 33. In other words, thestrand leaves each ridge at an acute angle. This may be readily observedin Fig. 3 in which the arrow 34 indicates the direction of movement ofthe strand in unwinding. This approach is favorable for reducing anytendency to tangling to the strands. The ridges 33 will appear in theouter portion of the rayon cake and will gradually become reduced andmay iinally almost disappear inward. But they will have a marked eiectin eliminating entanglement and tearing of the yarns especially at theouter portion of the cake in which this difculty has been most marked.And the substantial reduction of wearing of the outer portion of thecake will materially aid in realizing the advantage noted. The spacingbetween the ridges 38 is intended to tbe suiiicient to produce theundulated winding and to cause diierent resistances to be exertedagainst the centrifugal force of the strand so that the stratifiedreeling shall be effective for its intendedl purposes. Thus theresistance at the grooves will be less and cause less tension than atthe ridges 30.

I claim:

l. In an apparatus for making a cake of a hardened rayon strand forsubsequent washing and drying and unwinding of the cake, a whirlingbucket, and a removable, expansible liner therein, said liner havingmeans for frictionally gripping the cake to prevent rotary slippagethereof and deterioration of the outer portion of the cake, said linerbeing engaged and whirled by the bucket and being expansible afterremoval from the bucket for removal from the cake.

rayon yarn from lament extended hardened strands coiled into cake formfor subsequent washing, drying, and unwinding, the combination with awhirling bucket, reciprocable means for centrally feeding a strand tothe bucket, actuator means for whirling the bucket at high speed and forcausing reciprocation of said means at such a rate that the strand iscentrifugally uniformly laid on the wall of the bucket, and controlmeans on the inside of the bucket whirling therewith for upsetting theotherwise even path of winding of the strand to produce stratifiedreeling of the cake, a removable liner in the bucket engaged therewithso as to whirl with the buckt, said liner having said control meanscomprising generally annular projections arranged in parallel planes atan angleto the axis of the bucket, said liner being expansible uponremoval from the bucket to disengage the projections from the cake.

HARRY RUBINSTEIN.

2. In an apparatus for the manufacture ofv

